Electric current pulsating means



June 11, 195'7 Fig. 1

H. B AM 2,795,662 ELECTRIC CURRENT PULSATING MEANS Filed Feb.28, 1955 v- 20' .'17'32 y; 54 24a 24h [vl/enr:

- ,afar Ayef t ELECTRIC CURRENT PULSATING MEANS Hellmuth Bhm, Berlin-Charlottenburg, Germany, as-

signor to Licentia Patent-Verwaltungs-G. m. b. H., Hamburg, Germany Application February 28, 1955, Serial No. 491,120 Claims priority, application Germany March 4, 1954 s Claims. (ci. zoo-sz) It has been known to provide an electric current pulsing means of the liquid jet type, in which a motor and a pump member for the conductive liquid are housed in a common vessel. It has been further knovm to provide sepa- Irate chambers for the motor and for the pump member and to use an elastic or resilient shaft packing at the place where the motor shaft is passed through the separating partition. Though such design assures a satisfactory operation of the appartus, there is the disadvantage that the vessel has to be opened whenever access to the motor is necessary. Consequently, the entire vessel has to be evacuated and filled with a protective gas, if this is provided, after any such opening of the vessel.

It is an object of the present invention to provide for the motor shaft a novel bearing arrangement which has proven very satisfactory and assures an absolutely gastight seal `of the vessel for a long period of time.

According to this object of the invention the shaft bushing is provided with at least one elastic or resilient shaft seal and a radial bearing. Preferably, two resilient shaft seals are provided between which one or two radial bearings are disposed to rotatably mount the shaft. A dilusion of the outer air and the protective gas during the rotation of the shaft is prevented by suitably adjusting the pressure of said gas.

It is a further object of the present invention to do away with the common enclosure of the motor and pump member.

It is another object of this invention to provide a lubricated radial bearing above the shaft seal which is closest to the interior of the vessel.

It is a still other object of the invention to provide the drive shaft for the pump member at least partially with a surface ground to a high degree of smoothness, i. e., that part of the drive shaft which is located outside of the vessel containing the pump member and to provide at least one resilient shaft seal for this shaft.

Examples of the apparatus according to the invention are shown in the drawing, in which Figure 1 illustrates a longitudinal section through an embodiment of the invention;

Figure 2 is a longitudinal section through a part of a modification of the apparatus shown in Figure 1.

With reference to Fig. l of the drawing, 1 denotes a driving shaft for a pump member 8 which has the shape of an inverted certifugal cone and comprises a number of tube elements 8 spacedly mounted in this cone and diverging upwardly. When rotated this pump member 8 by means of its tube elements 8' throws conductive liquid jets against stationary electrodes 16 concentrically arranged around the shaft 1, this liquid being taken from a sump 9, preferably of mercury, into which the rotating pump member 8 partially immerses. This operation takes place under the action of the centrifugal force. Due to the rotation of the tube elements 8 and of the mercury jets issuing therefrom, intermittent electric connections are established between the mercury jets and the elec- States Patent O ice ltrodes 16, so that electric circuits connected therewith will be intermittently opened and closed to produce current pulses. 17 denotes conductive supports for the electrodes 16, said supports being passed through and carried by insulating bushings 18. The chamber containing the rotating pump member, |the stationary electrodes and the conductive liquid or mercury sump 9 is formed by a dished pot lil, the open top of which is covered and closed by a lid 11 through which the insulating bushings 18 with the conductive supports 17 for the electrodes 16 are passed. l

A resilient or elastic sealing ring 12 is lodged in and slightly projects from a groove provided in the lid 11 at a 'place adapted to sealingly engage a flanged portion 19 of the pot 10 vat its open top. A flange ring 14 engaging the lower side of this anged portion 10' is adapted to transmit thernecessary sealing pressure from bolts 27 to the sealing surface.

In the modification shown in Figure 2, illustrating only a part of the new apparatus, i. e. the sealing means for the pot 10, the wall at the edge or top of the pot 1d is turned back at 10 rather than being prvoided with a flange 10 as in Figure l. A resilient seal-ing ring 13 lodged in a groove of the lid 11 is spaced from the lid surface a-s clearly shown in Figure 2. The upper edge of the turned-back top of the pot 10 is adapted to enter the groove holding the sealing ring 13, when this upper edge is pressed on this sealing ring with the aid of a iiange ring 15 having a shape fitting the outer contour of the turned-back top.

The shaft 1 which is attached to a coupling 2 is rotatively mounted in an axial bearing 3 close to said coupling. 6 and 7 denote resilient or elastic seals for the shaft 1, while 4 and S illustrate two radial bearings for the same. These bearings 3, 4 and 5, and seals 6 and 7 are mounted in a bushing or sleeve 1 through which the shaft 1 is concentrically passed. This bushing or sleeve,

in Iturn, tits tightly in an opening in the lid 11 through which the sleeve 1 extends.

Practical tests have shown that it is of great importance for the proper operation of the apparatus to arrange the resilient shaft seal 7 below Ithe bearing 5 suitably made of sintered material. A ball bearing may be used in its place. If the arrangement of the seal 7 and the bearing 5 would be reversed, a paste will form between the mercury and the lubricant of the bearing. Such paste would harden in a short time causing the shaft to bind. In order to assure a superior rotatable mounting of the shaft 1, the second, likewise sintered bearing 4 is located very high. This bearing may also be replaced by a ball bearing.l A second resilient shaft seal or oil ring 6 is provided above said bearing 4, said ring 6 sealing the bearing 4 against the outside.

For continuous operation, the chamber between the bearings 4 and 5 is filled with lubricating grease, for example, Vaseline or oil in order to suiciently lubricate these two bearings. Furthermore, the lower resilient seal or oil ring 7 is fed with grease from the top, said grease illed in the upwardly enlarging cone-shape opening of the ring 7 assuring that the sealing lip is always supplied with sutiicient lubricant. The upper resilient shaft seal for oil ring 6 is supplied with lubricating grease from the top, the arrangement of the cone being the same as in the `oil ring 7, so that the lubricant will also in this ring lubricate the sealing lip in la perfect way. A 'suliciently large chamber for the lubricant is provided between the axial bearing 3 and the seal or oil ring 6.

The axial bearing 3 may be made of sintered metal requiring greasing only after longer intervals. if the bearings 4 and 5 are replaced by ball bearings, the axial bearing 3 may be omitted. When the surface of the Patented June 11, '1957 shaft 1 is ground accurately the sealing action will be superior and the lower shaft seal or oil ring 7 may be suiicient to assure a tight seal.

The conductive supportsy 17 of the stationary electrodes 16 and their insulating bushings 18 are sealed in a known manner in the lid 11. Two dat resilient or elastic sealing rings 24a and 2411 engaging one another in a horizontal plane are provided between the top of the lid 11 of the lower vessel 10 and a ange 20 of an Upper vessel 20. Electric leads or bus bars 25 are passed between these sealing rings 24a and 24b, said leads or bus bars connecting the conductive supports 1.7 of the elec. trodes 16 to an external circuit not shown in the drawing. In the same way, a rather thin or flat cannula may be inserted between the sealing rings Maand 24h, said cannular being adapted to supply the interior of the upper vessel 20 with a protective gas. Such design has the advantage that it is not necessary to provide separate in:

sulating and sealing means for'the electric conduits .andl

for `the cannula. Flat bus bars as conventionally used in high voltage apparatus can be readily employed in the new device making it possible that the electric current is conducted to the electrodes 16 in the interior of the lower vessel 10 practically without losses in electric en ergy. The insertion of the bus bars does not impair the sealing `action of the resilient rings 24a and 2413.

The upper vessel 2Qv contains the motor 21 having a motor shaft (not shown) connected to the coupling 2, from which the driving 'shaft 1 extends, said motor being held by the upper Wall of this vessel 20, and terminals 17 connecting the ends of the bus bars 25 projecting into) this vessel to the conductive supports 17. The sealing rings 24a and 24b are tightly pressed on one another except at the places where the bus bars 25 or the cannula 26 are inserted. The latter can be removed after lling of the chamber inside the vessel 20 with the protective gas without breaking the seal. The rings 24a and 24h are advantageously lodged in grooves provided opposite one another in the Asurfaces of the top of the lid 11 and of the flange 20' of the vessel 20, respectively. The same bolts 27 are used to exert the sealing pressure on the sealing rings 24a and 24'b and to. assemble the vessel 20 as are employed for the mounting of the lid, 11 and sealing of the pot 10. These bolts 27 are passed through aligned holes in the respective parts of the apparatus as shown in Figure 1 of the drawing. A

While specific embodiments of the invention have Vbeen shown in the foregoing, I do, not limit myself to the. exact details'of construction set forth, and the, invention 4 embraces such changes, modifications and equivalents of the parts and their formation and arrangement as come within the purview of the appended claims.

I claim:

1. In a liquid contactor of the type described, a lower vessel having a lid sealed thereon, a conductive liquid partially iilling said vessel, a protective gas lling the remaining space within said vessel, a centrifugal pump meansin said vessel, said pump means having a substantially vertical'axis, 'said pump means also having at least one suction inlet immersed in said liquid and at least one ejector element above said liquid for discharging said'liquid within said vessel in form of a continuous jet, at least one stationary contact means mounted in said vessel in the path o f said jet, an upper vessel on top of said lower vessel and Isealed thereon, a motor in said upper vessel having a driving shaft operatively connected with said pump means, bearing means in said vessels to journal said shaft and pass it through said lid from said upper vessel to said lower vessel, at least one shaft seal in Vysaid bearing means preventing leakageA of gases between said vessels, said upper vessel being iilledY with a protective gas under a pressure which is balancing the pressure of said protective `gas in said lower vessel in such a manner that the sealing action of said resilient shaft seal is increased.

2. In a liquid contacter according to claim Yl, said two vessels having said lid as common partition sealed thereon,

at least two superimposed electric insulating sealing rings between said partition and said upper vessel, electric leads passed between two of said rings from the outside and conneetable to said contact means inside said vessels.

3. In a liquid contacter according to claim 1, said` bearing means comprising a sleeve passingthrough lsaid lid from said uppervessel to said lower vessel, and at least one resilient shaft seal combined with a radial bearing and inserted in said sleeve to rotatably and tightly mount said shaft in said sleeve. 

